I am requesting support to continue study on ribosomes from Bacillus. Two major areas of investigation are proposed: (a) the timing of the synthesis of the polysomes of spores, and their disappearance on germination and outgrowth; (b) a comparison of the components present in ribosomes of spores and vegetative cells. These experiments should reveal the part of the life cycle during which mRNA of spore polysomes is synthesized, when the "defects" in spore ribosomes first appear, and the cause of the "defects."